1. Field of the Invention
The present invention relates to a valve apparatus having internally installed valves, wherein the valve apparatus includes a block having flow passages formed therein and another block, the blocks being connected together while gripping a seal member therebetween.
2. Description of the Related Art
In food processing devices and the like that are used at food manufacturing sites, for example, it is essential to perform cleaning and disinfecting operations using water and/or water-based cleansers. Accordingly, a fluid pressure driven device such as a fluid pressure cylinder or the like is integrated within such food processing devices, wherein water resistance of the fluid pressure driven device also is necessary.
The fluid pressure driven device is driven by supplying air, for example, as a driving pressure fluid (operating fluid). In this case, it is generally conventional to arrange a valve apparatus, which serves to appropriately switch the destination of flow of the fluid with respect to the fluid pressure driven device, in the vicinity of the fluid pressure driven device. Accordingly, in the food processing device or the like, it also becomes necessary for the valve apparatus to be water resistant.
Incidentally, in this type of valve apparatus, there are generally a large number of joints and gaps that interconnect a plurality of valves. In the case of a food processing device or the like, liquid and solid materials can become trapped and collect within surface irregularities produced by such joints and gaps. Accordingly, in the case that cleaning is performed using a high pressure cleaning apparatus to clean and remove such collected liquids and solids from the irregular surface portions of such joints and gaps, water and detergents enter into the interior of the valve unit, raising the possibility that damage may occur to the valve unit.
In Japanese Laid-Open Patent Publication No. 2001-254859, a solenoid manifold for use in a food processing device is proposed, in which by individually placing the valves one-by-one within a casing in a capsule form, a manifold valve is structured in which the accumulation and retention of liquids does not occur. In this case, a waterproof seal member is arranged between surfaces of the casing and the valve mounts.
Notwithstanding, with the structure disclosed in Japanese Laid-Open Patent Publication No. 2001-254859, in order to prevent accumulation and retention of liquids between each of the valve units (capsules), it is essential for the pitch between each of the valve units to be sufficiently wide, causing a problem that the valve apparatus becomes large in size. In the aforementioned manner, liquids such as collected water, detergents and the like elicit propagation of unwanted bacteria, raising concerns about health and sanitation.
Furthermore, in this type of valve apparatus, which is intended to improve water resistance, although on the one hand the apparatus is highly hermetic and airtight, numerous inconveniences related to disassembly, and in particular maintenance, of the apparatus occur. For example, in the event that a specified valve needs to be exchanged, the replacement operation therefor is quite complicated.